Sliding switch assembly with spring-biased contact and multi-sectional housing

ABSTRACT

This invention relates to an electrical switch structure comprising a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, a plurality of slides adjustably arranged within the housing structural elements, each housing structural element being provided with at least one pair of contacts fixedly mounted therein, each slide being freely adjustable to any position in any of the housing structural elements, each slide adapted to engage only a single pair of contacts at any one particular position, and a removeable cover closing the interior of the housing.

United States Patent 1191 3,735,059 May 22, 1973 Glaser et al.

[54] SLIDING SWITCH ASSEMBLY WITH 3,251,956 5/1966 Rasor et a1 ..200/168 K SPRIN(; BIASED CONTACT AND 3,514,554 5 1970 Boysen ..200/168 K MULTI'SECTIONAL HOUSING FOREIGN PATENTS OR APPLICATIONS [75] Invemms Karl Glaser Staten/Elder; 1,100,801 1/1968 Great Britain ..200/168 K Sung, Esslmgen, 2,000,946 9/1969 France ..200 168 K Germany [73] Assignee: EBE Elektro-Bau-Elemente Gmbl-l, Examiner j- Scott Stetten/Filder, Germany Attorney-George F. Dvorak et al.

[22] Filed: Nov. 16, 1971 57 ABSTRACT PP 93 This invention relates to an electrical switch structure comprising a housing including a plurality of U-shaped 52 us. Cl. ..200/16 0, 200/168 K i sirucmral elements Side'by'side relatIonshIp, a pluralIty of slIdes ad ustably arranged [51] Int. Cl. ..H0lh 15/00, HOlh 9/02 h l h h Field of Search 200/11 D l 6 168 K wIthIn the ousmg structura elements, eac ousmg structural element bemg provided wIth at least one pair of contacts fixedly mounted therein, each slide [56] References cued being freely adjustable to any position in any of the UNITED STATES PATENTS housing structural elements, each slide adapted toengage only a single pair of contacts at any one partIcu- 3.536.795 1971 M ntel et al. ..200/l68 K X lar.positi0n, and a removeable cover closing the interi- 2,528,035 10/1950 Clayton or e housing 3,238,319 3/1966 Godel et al.

2,488,670 l1/1949 Koenig ..200/16 C 22 Claims, 14 Drawing Figures PATENIEumzzlsrs 4 SHEET 2 OF 5 PATENTEDHAYEZIBB III] II SHEET 3 BF 5 SLIDING SWITCH ASSEMBLY WITH SPRING-BIASED CONTACT AND MULTI-SECTIONAL HOUSING BACKGROUND OF THE INVENTION A sliding switch having contact pairs and square housing structural elements is generally known from German Auslegeschrift No. 1,245,475 wherein there is generally shown a switch having a slide to be operated from the outside, and a contact bridge provided within each housing structural element. Several such housing structural elements can be put together to form an entire housing.

The disadvantages of the known sliding switch is that all of the slides can only be operated together by means of an operating pin, and that the slide located within a housing structural element can only be moved within this individual element and not within the entire switch structure.

In the case of a further known switch socket for electrical devices, especially for control stations having push-type operation, German printed specification No. 1,154,174 generally discloses U-shaped contact column pairs which can be put together with similar elements in the form of building blocks. The contact bridges here are also actuated by means of an operating rod which is common to all slides so that an independent operation of the slides it not possible, and further, a sliding of the slides to desired contact pairs within the housing is not possible either.

SUMMARY OF THE INVENTION It is an object of the invention to provide a switch which can be put together from building blocks which differ from each other in the least possible way, and which provides a great variety for various switching possibilities. The switch in accordance with the invention is intended to be ready for use after assembly of the desired separate elements and their desired complementary arrangement without the danger of unintentional misadjustment externally of the switch. The switch thus belongs to that group of switches which are set for a certain program before use, and can be re-set for further programs after termination of said certain program. This type of switch is used predominantly in card technology.

To solve this problem, the invention provides that each housing structural element is provided with at least one and usually not more than two or three fixed contact pairs, and each slide is freely slidable within the entire housing. Each slide is of such a width that two neighboring slides can bridge two neighboring contact pairs. The interior of the housing is closed by a readily removeable cover. On the basis of this construction, sliding switches having an optional number of contact pairs can be realized from only two different housing structural elements and one type of slide. Numerous switching problems can be solved in a simple manner with the sliding switch in accordance with the invention in view of the fact that the slides can be slid as desired within a housing composed of housing structural elements. Misadjustment in later operation is excluded by closing the sliding switch with the cover, after which it is ready for operation. The sliding switch can also be quickly readjusted if desired or necessary by removing the cover, so that the switch can be used at all times for solving further switching problems after having fulfilled a particular switching task. The invention thus provides a sliding switch which is not only very economical in production but also economical and quick in use and also operates with exceptional realiability. It can be used to special advantage in installations where the setting of different programs is necessary but where each such program is intended to remain unchanged for a certain length of time.

The present switch employs slides which can be inserted or removed through an open side of said hous ing, after which the housing can be closed with a cover. On the basis of this construction, the entire housing can be constructed from individual housing structural elements while the desired number of slides need not be placed in the desired positions until later during the assembly process.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be further described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a side elevational view of a sliding switch in accordance with the invention composed of three housing structural elements and two end covers;

FIG. 2 is a partial plan view of the housing of the sliding switch with the cover removed;

FIG. 3 is an end elevational view looking in the direction of arrow III in FIG. 1;

FIG. 4 is a longitudinal cross-sectional view partially broken away taken along the longitudinal axis of FIG. 1 and illustrating the left-hand portion of the invention as viewed in FIG. 1;

FIG. 5 is a cross-sectional view taken along line V-V in FIG. 4;

FIG. 6 is a plan view of a housing structural element of the sliding switch before mounting the fixed contacts;

FIG. 7. is a cross-section view of a housing structural element of the sliding switch taken along a plane located adjacent the fixed contacts;

FIG. 8 is a cross-section view of a housing structural element of the sliding switch taken along a plane located between the fixed contacts;

FIG. 9 is a plan view of a slide for the sliding switch;

FIG. 10 is a cross-section view of a further preferred embodiment of the sliding switch in accordance with the invention;

FIG. 11 is'a cross-sectional view of a mounted end cover having a special mounting plate;

FIG. 12 is an end elevational view of the mounted end cover having the special mounting plate as seen in FIG. 11;

FIG. 13 is a plan view of a slide having a cover used as a tool; and

FIG. 14 is a plan view of a preferred embodiment of a connecting member for the sliding switch illustrated in FIG. 10.

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to FIGS. 1 through 5, the housing 11 of the sliding switch in accordance with the invention is composed of individual housing structural elements 16 and 17, end covers 20, and a cover 12 closing the housing on the top side.

As can best be seen in FIGS. 2 and 4, several slides 13, 13', 13" are arranged in succession in the interior of the housing along its longitudinal axis, which slides have bores 19 (FIG. 4) in the region of their middle portion to permit the passage therethrough of a bolt 18 extending longitudinally in the housing which has its end portions firmly fixed to the housing and upon which the slides 13, 13', 13" are slidably guided. Each of the slides 13, 13', 13" have on the undersides thereof a contact bridge 15, 15', 15" (FIG. 4) which each have lateral guide posts 43 (FIG. extending into the interior of the associated slide and which are urged against contact pairs 14, described in detail later in this description, by a compression spring 44 associated with each slide and positioned between the lateral guide posts. Each of the contact bridges 15, 15" work together with the rigid contact pairs 14 which are mounted in the base 39 of the housing structural elements 16 and 17.

The bolt 18 not only extends through the bores 19 in the slides 13 but also extends through bores 21 in the end covers which bores are axially aligned with the bores 19. One end (not shown) of the bolt 18 may have a conventional screw head or can be threaded and provided with a nut 22 as on the other end of the bolt as shown in FIG. 4. By adjusting the nut 22, the housing structural elements 16 and 17 as well as both end covers 20 can be firmly braced and secured against one another.

As best seen in FIG. 5, the housing structural elements 16 and 17 are each of rectangular cross section having a base 39 and opposed side walls 23 and 24. The correspondingly shaped slide 13 is provided in the upper portion thereof with a bore transverse to the longitudinal axis of the housing 11 extending therethrough and having a compression spring 27 disposed therein, which spring acts on retaining balls 26 supported at both ends of the spring and moveably engaging recesses having bevels 34 (FIGS. 2 and 6) located in the side walls 23 and 24 with which the retaining balls 26 coact. The recesses 25 and bevels 34 are in effect grooves which extend vertically upwardly from the contact pairs 14. As seen in FIGS. 2 and 6, the borders of these grooves have bevels 34 so that the balls 26 engaged therein can be readily moved out of the groove-like recess by exerting a longitudinal force on the slide 13.

As seen in FIGS. 5, 6 and 7, openings 28 are provided in the base 39 of each housing structural element 16 and 17, the openings being adjacent the side walls 23 and 24 and aligned with the groove-like recesses 25. A slot extends horizontally away from 'each'opening 28, each slot terminating in an opening 36 extending from the interior space 31 of the housing 12 to a depression 37 in the base 39.

As best seen in FIG. 5, the contact pairs 14 each comprise generally U-shaped curved profiles having legs of different length. The long leg is inserted downwardly through the openings 28. This is readily possible due to the alignments with the recesses 25 in the side walls 23, 24. With the body portion received in the slot 35, the short leg 38 of the contact pairs is arranged so that it passes through the bores 36. After the fixed contact 14 has been inserted, the end of the short leg 38 is bent outwardly until it abuts on the beveled walls 42 of the depression 37 in the base 39 thereby securing the fixed contacts to the housing structural element 16, 17. The contact pairs 14 are symetric about the longitudinal axis 40 of the housing 11. The depth of the slot 35 is such that the contact surface 41 of the contact pairs 14 projects slightly upwardly above the base 39 and into the interim space 31 of the housing 11.

As seen in FIG. 4, the top transverse edges of the slides 13 have notches 29 into which stops 30 can be inserted, the stops 30 being transversely mounted in slots 33 (FIGS. 2, 6 and 8) of the side walls 23, 24 so as to be non-slidable. The stops 30 serve as lugs for inserted slides 13 in order that these slides may be secured in a certain position in the housing 12 in additionto the positioning securement obtained by the retaining balls 26 thereby excluding any unintentional sliding of the slides 13 in the housing 11.

As seen in FIGS. 7 and 8, the inner interior space 31 of the housing 12 has transverse enlargements 32 at the very top which serve to receive the-cover 12. The side walls of the enlargements 32 proceed from the bottom to the top somewhat obliquely towards the inside in order that the cover can be snapped into position by a springlike effect and can thus be easily inserted or removed.

As seen in FIGS. 3 and 4, nuts 46 are fixedly mounted in the end covers 20 such that the entire sliding switch can be firmly mounted on a mounting plate 54 by means of mounting bolts 55. Both ends of the bolt 18 with nut 22 secured thereon, as well as the nut 46 are sunk in a recess 45 of the end cover.

Referring to FIG. 1, the side walls of the end covers 20 and housing 12 have steps 47 provided therein which engage each other in a manner to effectively prevent any twisting of the housing structural elements 16, 17 and the end covers 20. As seen in FIG. 6, a projection 57 is provided on one side of the end wall 23, and a notch 58 is provided on the opposite side of the end wall 23. The side wall 24 has the same projections 57 and notches 58 but arranged in the opposite positions from those on end wall 23. The projections 57 and notches 58 are designed such that the projections 57 match the corresponding notches 58 of neighboring housing structural elements 16, 17. This arrangement of the projections and notches permits the side walls of each housing structural element to be exchanged with the others without impairing the match of neighboring housings.

As seen in FIGS. 5 and 7, the slides 13 have transversely extending guide projections 49 (FIG. 5) at the top which abut on guide steps 48 longitudinally extending along the side walls 23, 24 after the slide has been inserted into the housing 12. The guide projections 49 and the guide steps 48 are arranged such that the underside of the insulating portion of each of the slides 13 is positioned a predetermined distance from the base 39 of the housing 11 so that the underside of the insulating portion of the slides 13 is prevented from touching the contact pairs 14. The purpose of the guide projections 49 is to prevent the bolt 18 from being bent while sliding the slide 13 therealong and to achieve a more stable and more compact structure.

As seen in FIGS. 2 and 4, both of the slides 13 and 13" are slidably connected with one another in a longitudinal direction by a connecting member 51. A recess 50, in addition to the notches 29, are provided in the top surface of the slides 13 for receiving the connecting member 51 such that a projecting pin portion 53 remains projecting from the middle of the top surface of the slide. The connecting member 51 is flat having a height approximately equal to the projecting height of the pin 53, and has several openings 52 spaced apart a distance equal to the spacing between adjacent contact pairs 14 and adapted to fit over the pins 53. The connecting member 51 thus can readily be placed onto neighboring or spaced slides 13 and rigidly connects these with one another in a longitudinal direction. One or more slides 13 can be connected with one another at the desired distance by the connecting member 51.

As seen in FIGS. 1 and 8, spaced notches 56 are provided at the upper edge of the side walls 23, 24 of the housing structural elements 16, 17 and extend under the cover 12. This design permits the easy lifting of the cover from its spring-loaded anchoring by meansof inserting a tool into the slot between the notches and the underside of the cover.

In assembling the sliding switch, the end covers 20 and the necessary slides 13 are put together with the housing structural elements 16, 17 necessary for the desired switch. Thereafter, the bolt 18 is inserted transversely through the entire arrangement, after which the housing structural elements and end covers are braced tightly against one another by tightening the nut 22 on the bolt. Thereafter, the slides 13 are brought into their desired positions by sliding them along the bolt 18. If necessary or if desired, the slides can be connected by means of connecting member 51 or can be fixed by stops 30. As soon as all parts are arranged in the desired positions, the cover 12 is snapped into position and the switch is then ready for use.

A special advantage of the sliding switch in accordance with the invention is that only a very limited number of variously designed individual parts is necessary to solve a large number of different switching problems involving a varying number of switches required. Accordingly, only housing structural elements l6, l7, slides 13, end covers 20, and various length bolts 18 as well as various length covers 12 need be kept in stock. In addition, to assure diversity, various designs of the connecting members 51 and the stops 30 can also be kept in stock. 7

Furthermore, the subject matter of the invention is worthy of notice in that a very compact structure is achieved by the particularly expedient arrangement of the various recesses and projections. For example, the connecting members 51 and stops 30 do not necessitate an enlargement of the outer dimension of the entire switch.

A further preferred embodiment of the sliding switch is shown in FIG. 10 in which thesame parts are designated with the same reference numerals as in the afore described figures. In the embodiment according to FIG. 10, the slide 13 projects above the upper rim of the housing structural element 16 while cover'12' has side walls 12a, 12b which also completely enclose the upwardly projecting portion of the slide 13. The slide can easily be operated in this way when the cover is removed.

Furthermore, the top surface of the slide 13 and the underside of cover 12 are designed asymmetrical to the longitudinal axis 40 of the housing 11 so that the cover cannot be reversed and can only be put on the housing when it is in the correct position relative to the inserted slide.

The inner sides 60a and 60b of side walls 12a, 12b of the cover 12' are slightly beveled, as are the corresponding parts of the housing structural element 16, to improve the seating of the cover.

The contact bridges 15 have projections 62 in the area of the contact pairs 14 adapted to engage in slots 61 formed in the contact pairs 14 thereby ensuring a firm engagement therebetween. The contact bridges are urged downwardly by springs 44a and 44b. In this manner no special position securement means are required as were necessary in the previous embodiment.

An especially expedient possibility for mounting the sliding switch in accordance with the invention on a mounting plate 54 is illustrated in FIGS. 11 and 12. A substantially rectangular metal mounting bracket 65 having a vertically extending slot 71 in the area of the opening for the bolt 18 is inserted into a correspondingly constructed substantially rectangular recess on the outer side of the end cover 20. The mounting bracket 65 has a projection 66 on the underside thereof, which serves to extend through an opening 73 in a mounting plate 54, and which'is then bent over to engage the mounting plate thereby securing the switch thereto in the position shown in FIG. 11 by the dotdash line.

As seen in FIG. 12, a tab 67 is provided on the end cover 20, which can cooperate with two recesses of the mounting bracket 65, the height of the recesses being offset relative to one another. In the position shown in FIG. 12, the mounting bracket 65 is flush with the sliding switch. In the position illustrated by the dot-dash line in FIG. 12, which is reversed by the mounting bracket 65 projects slightly downwardly from the sliding switch so that a predetermined spacing remains be tween the mounting plate 54 and the underside of the sliding switch when the same is mounted thereon, this spacing serving to insulate the sliding switch against heat produced during soldering of the contact pairs 15 and, moreover, permits the gases formed during the soldering procedure to escape more easily.

Referring to FIG. 13 there is shown how the cover 12' can be additionally used as a tool for sliding the slide 13 by suitably designing the cover so that one side fits into an H-shaped recess 63 formed in the top surface of each slide 13. FIG. 14 shows the connecting member 51 as used for connecting several slides 13.

What is claimed is:

1. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing elements having side walls and a bottom wall disposed therebetween, at least one sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being freely adjustable in a longitudinal direction to any position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, and a readily removeable and replaceable cover closing the interior of the housing.

2. A switch according to claim 1, wherein said sliding contact means can be readily inserted, removed, or adjusted through an open longitudinal side of said housing, said side being closed by said cover.

3. A switch according to claim 1, wherein a rod extending longitudinally of said housing is fixedly mounted in said housing in a stationary manner, said sliding contact means having bores extending completely therethrough in the longitudinal direction of the housing, and said rod extending through said bores in said sliding contact means to supportively guide the sliding contact means in the housing.

4. A switch according to claim 3, wherein said housing has opposed ends, end covers closing said opposed ends, said end covers having bores therein through which said rod extends, one end of said rod fixedly engaging one of said end covers with the other end of said rod being threaded and having a nut threadedly received thereon and engaging said other end cover so as to secure said end covers to said housing.

5. A switch according to claim 1, wherein latch means are provided for releasably latching each sliding contact means at a selected position adjacent a selected one of said fixed contact pairs to electrically bridge the same.

6. A switch according to claim wherein said housing structural elements have opposed substantially parallel side walls interconnected at their lower ends by a bottom wall, said fixed contact pairs being mounted in spaced positions along said bottom wall, beveled grooves formed in each side wall perpendicular to and extending from the bottom wall and positioned immediately above each fixed contact pair, and said sliding contact means having spring-loaded retaining balls projecting transversely from opposite sides of said sliding contact means for engagement in said grooves.

7. A switch according to claim 1, wherein said sliding contact means have notches therein extending transversely to the longitudinal axes of said housing, and stops adapted for insertion into said housing transversely of the same and adapted to engage said notches for retaining said sliding contact means in selectable positions in said housing relative to said fixed contact pairs.

8. A switch according to claim 1, wherein said sliding contact means includes a contact bridge supported from the bottom thereof, said housing structural elements include opposed side walls and a bottom wall interconnecting the same, said fixed contact pairs mounted in said bottom wall and longitudinally spaced therealong, said fixed contact pairs having depressions formed therein opening inwardly of said housing, and said contact bridge having projections extending outwardly therefrom complementary to said depressions for releasable engagement therewith to retain the sliding contact means in position relativeto the engaged fixed contact pair.

9. A switch according to claim 8, wherein said contact bridge is U-shaped, the legs of said U-shaped contact bridge extending toward said top surface of said sliding contact means, and resilient spring means associated with said contact bridge for resiliently urging said contact bridge outwardly away from said sliding contact means toward the bottom wall of said housing structural elements.

10. A switch according to claim 1, wherein said housing includes end covers mounted at opposed ends of said housing, and a mounting plate fixedly secured to each end cover and having a portion projecting outwardly therefrom so as to be engageable with a mounting surface for securing the switch thereto.

11. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed substantially parallel side walls interconnected at their lower ends by a bottom wall, at least one sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, said sliding contact means each having a contact bridge supported at the bottom thereof and adapted for engagement with a pair of said fixed contacts to electrically bridge the same, each said contact bridge adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, said fixed contacts being approximately U-shaped and having a long leg and a short leg portion, first openings in said bottom wall adjacent each side wall for receiving said long leg portion, second openings in said bottom wall spaced inwardly from said first openings for receiving said short leg portion, and a groove-shaped recess formed in each side wall immediately above and aligned with said first openings and extending from said bottom wall completely along said side wall to the top thereof.

12. A switch according to claim 11, wherein said first and second openings in said bottom wall are interconnected by a recess formed along the interior surface of said bottom wall, said second opening extending from the interior of the housing to the exterior of the same and terminating at the exterior in a depression formed in the exterior surface of said bottom wall, said depression having a wall surface adapted for engagement with said short leg of said fixed contact so that said short leg is pressed against said wall surface thereby preventing the removing of said fixed contact from its mounted po sition in said bottom wall.

13. A switch according to claim 1, wherein each of said sliding contact means include a contact bridge supported at the bottom thereof and adapted to bridge and interconnect a pair of said fixed contacts when said sliding contact means is moved into juxtaposition with the pair of said fixed contacts.

14. A switch according to claim 1, wherein said housing structural elements have opposed substantially parallel side walls interconnected at their lower ends by a bottom wall, a pair of end covers adapted for engagement with the outermost ends of the housing for retaining said housing structural elements therebetween, said end covets including side walls adapted to engage said side walls of the adjacent housing structural elements, said end cover side walls and said housing structural element side walls each having matching steps formed therein to prevent any twisting of the housing structural elements and to ensure the alignment of said end covers and said housing structural elements during the assembly of the same.

15. A switch according to claim 1, wherein said housing includes generally opposed substantially parallel side walls, a bottom wall interconnecting the bottom end portions of said side walls and being generally perpendicular thereto, a longitudinally extending recess formed in the upper interior edges of said opposed side walls and longitudinally extending therealong, opposed projections transversely extending from the top surfaces of said sliding contact means and adapted to slidably engage said recesses in said side walls so as to longitudinally guide the sliding movement of the sliding contact means in said housing along said recesses.

16. A switch according to claim 1, wherein connecting means are provided for selectably connecting at least two sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto.

17. A switch according to claim 16, wherein said housing structural elements are generally U-shaped having opposed side walls and a bottom wall extending therebetween, a cover adapted to close the open-end of said U-shaped structural elements, said cover and said connecting means being provided with complementary recesses and projections so that said connecting means can be positioned on said sliding contact means for interconnecting the same without interference with said cover.

18. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, connecting means for connecting at least two of said sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto, a cover adapted to close the open-end of said U-shaped housing structural elements, said cover and said connecting means having complementary recesses and projections so that said connecting means can be positioned on said sliding contact means for interconnecting two or more sliding contact means without interference with said cover, said sliding con tact means each having a top surface provided with a pin projecting perpendicular thereto, said connecting means including a connecting member being of a thickness corresponding to the height of projection of said pin, and an opening in said connecting member for receiving said pin on said sliding contact means when said connecting member is mounted on said sliding contact means.

19. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, connecting means for connecting at least two of said sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto, a cover adapted to close the open-end of said U-shaped housing structural elements, said cover and said connecting means having complementary recesses and projections so that said connecting means can be positioned on said sliding contact means for interconnecting two or more sliding contact means without interference with said cover, an H-shaped recess provided in the top surface of said sliding contact means, said connecting means including a connecting member consisting of a pair of spaced longitudinally extending sidebars interconnected by transversely extending crossbars at spaced points therealong, said crossbars being of a shape to fit within at least one of the portions of said H-shaped recess so as to interconnect two or more of said sliding contact means.

20. A switch according to claim 19, wherein said housing structural elements are U-shaped having opposed side walls and a bottom wall interconnecting the same, a generally U-shaped cover adapted for engagement with the top portions of said side walls for closing said housing, and said cover having a leg portion adapted to engage said H-shaped recess on said top surface of said sliding contact means for engaging the same and sliding said sliding contact means into position in said housing.

21. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, connecting means for connecting at least two of said sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto, a cover adapted to close the open-end of said U-shaped housing structural elements, said cover and said connecting means having complementary recesses and projections so that said connecting means can be positioned on said sliding contact means for interconnecting two or more sliding contact means without interference with said cover, said connecting means is adapted for connection to said sliding contact means at spaced apart distances equal to the distance between two adjacent pairs of fixed contacts such that upon positioning one of said interconnected sliding contact means adjacent one pair of said fixed contacts then the sliding contact means connected thereto by said connecting means will simultaneously also be in proper adjacent position with a pair of said fixed contacts.

22. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, said housing includes end covers mounted at opposed ends of said housing, a mounting plate fixedly secured to each of said end covers with a portion projecting outwardly therefrom for engagement with a mounting surface for securing the switch thereto, said end covers including a tab projecting outwardly therefrom, said mounting plate having two recesses formed therein and adapted so that one recess will engage the tab in one position of said mounting plate with the other recess engaging the tab upon the reversal of the mounting plate said first recess being offset on said mounting plate from said second recess so that in a first position of said mounting plate said first recess will be engaged by said tab on said end cover with the bottom of said recess being flush with the bottom wall of said housing, and upon reversal of 180 of said mounting plate said second recess will be engaged by said tab at which time said mounting plate will project slightly outwardly beyond the bottom wall of said housing thereby effecting the spacing of said bottom wall from the mounting surface upon the mounting of said switch thereon. 

1. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing elements having side walls and a bottom wall disposed therebetween, at least one sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being freely adjustable in a longitudinal direction to any position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, and a readily removeable and replaceable cover closing the interior of the housing.
 2. A switch according to claim 1, wherein said sliding contact means can be readily inserted, removed, or adjusted through an open longitudinal side of said housing, said side being closed by said cover.
 3. A switch according to claim 1, wherein a rod extending longitudinally of said housing is fixedly mounted in said housing in a stationary manner, said sliding contact means having bores extending completely therethrough in the longitudinal direction of the housing, and said rod extending through said bores in said sliding contact means to supportively guide the sliding contact means in the housing.
 4. A switch according to claim 3, wherein said housing has opposed ends, end covers closing said opposed ends, said end covers having bores therein through which said rod extends, one end of said rod fixedly engaging one of said end covers with the other end of said rod being threaded and having a nut threadedly received thereon and engaging said other end cover so as to secure said end covers to said housing.
 5. A switch according to claim 1, wherein latch means are provided for releasably latching each sliding contact means at a selected position adjacent a selected one of said fixed contact pairs to electrically bridge the same.
 6. A switch according to claim 5 wherein said housing structural elements have opposed substantially parallel side walls interconnected at their lower ends by a bottom wall, said fixed contact pairs being mounted in spaced positions along said bottom wall, beveled grooves formed in each side wall perpendicular to and extending from the bottom wall and positioned immediately above each fixed contact pair, and said sliding contact means having spring-loaded retaining balls projecting transversely from opposite sides of said sliding contact means for engagement in said grooves.
 7. A switch according to claim 1, wherein said sliding contact means have notches therein extending transversely to the longitudinal axes of said housing, and stops adapted for insertion into said housing transversely of the same and adapted to engage said notches for retaining said sliding contact means in selectable positions in said housing relative to said fixed contact pairs.
 8. A switch according to claim 1, wherein said sliding contact means includes a contact bridge supported from the bottom thereof, said housing structural elements include opposed side walls and a bottom wall interconnecting the same, said fixed contact pairs mounted in said bottom wall and longitudinally spaced therealong, said fixed contact pairs having depressions formed therein opening inwardly of said housing, and said contact bridge having projections extending outwardly therefrom complementary to said depressions for releasable engagement therewith to retain the sliding contact means in position relative tO the engaged fixed contact pair.
 9. A switch according to claim 8, wherein said contact bridge is U-shaped, the legs of said U-shaped contact bridge extending toward said top surface of said sliding contact means, and resilient spring means associated with said contact bridge for resiliently urging said contact bridge outwardly away from said sliding contact means toward the bottom wall of said housing structural elements.
 10. A switch according to claim 1, wherein said housing includes end covers mounted at opposed ends of said housing, and a mounting plate fixedly secured to each end cover and having a portion projecting outwardly therefrom so as to be engageable with a mounting surface for securing the switch thereto.
 11. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed substantially parallel side walls interconnected at their lower ends by a bottom wall, at least one sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, said sliding contact means each having a contact bridge supported at the bottom thereof and adapted for engagement with a pair of said fixed contacts to electrically bridge the same, each said contact bridge adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, said fixed contacts being approximately U-shaped and having a long leg and a short leg portion, first openings in said bottom wall adjacent each side wall for receiving said long leg portion, second openings in said bottom wall spaced inwardly from said first openings for receiving said short leg portion, and a groove-shaped recess formed in each side wall immediately above and aligned with said first openings and extending from said bottom wall completely along said side wall to the top thereof.
 12. A switch according to claim 11, wherein said first and second openings in said bottom wall are interconnected by a recess formed along the interior surface of said bottom wall, said second opening extending from the interior of the housing to the exterior of the same and terminating at the exterior in a depression formed in the exterior surface of said bottom wall, said depression having a wall surface adapted for engagement with said short leg of said fixed contact so that said short leg is pressed against said wall surface thereby preventing the removing of said fixed contact from its mounted position in said bottom wall.
 13. A switch according to claim 1, wherein each of said sliding contact means include a contact bridge supported at the bottom thereof and adapted to bridge and interconnect a pair of said fixed contacts when said sliding contact means is moved into juxtaposition with the pair of said fixed contacts.
 14. A switch according to claim 1, wherein said housing structural elements have opposed substantially parallel side walls interconnected at their lower ends by a bottom wall, a pair of end covers adapted for engagement with the outermost ends of the housing for retaining said housing structural elements therebetween, said end covers including side walls adapted to engage said side walls of the adjacent housing structural elements, said end cover side walls and said housing structural element side walls each having matching steps formed therein to prevent any twisting of the housing structural elements and to ensure the alignment of said end covers and said housing structural elements during the assembly of the same.
 15. A switch according to claim 1, wherein said housing includes generally opposed substantially parallel side walls, a bottom wall interconnecting the bottom end portions of said side walls and being generally perpendicular thereto, a longitudinally extending recess foRmed in the upper interior edges of said opposed side walls and longitudinally extending therealong, opposed projections transversely extending from the top surfaces of said sliding contact means and adapted to slidably engage said recesses in said side walls so as to longitudinally guide the sliding movement of the sliding contact means in said housing along said recesses.
 16. A switch according to claim 1, wherein connecting means are provided for selectably connecting at least two sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto.
 17. A switch according to claim 16, wherein said housing structural elements are generally U-shaped having opposed side walls and a bottom wall extending therebetween, a cover adapted to close the open-end of said U-shaped structural elements, said cover and said connecting means being provided with complementary recesses and projections so that said connecting means can be positioned on said sliding contact means for interconnecting the same without interference with said cover.
 18. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, connecting means for connecting at least two of said sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto, a cover adapted to close the open-end of said U-shaped housing structural elements, said cover and said connecting means having complementary recesses and projections so that said connecting means can be positioned on said sliding contact means for interconnecting two or more sliding contact means without interference with said cover, said sliding contact means each having a top surface provided with a pin projecting perpendicular thereto, said connecting means including a connecting member being of a thickness corresponding to the height of projection of said pin, and an opening in said connecting member for receiving said pin on said sliding contact means when said connecting member is mounted on said sliding contact means.
 19. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, connecting means for connecting at least two of said sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto, a cover adapted to close the open-end of said U-shaped housing structural elements, said cover and said connecting means having complementary recesses and projecTions so that said connecting means can be positioned on said sliding contact means for interconnecting two or more sliding contact means without interference with said cover, an H-shaped recess provided in the top surface of said sliding contact means, said connecting means including a connecting member consisting of a pair of spaced longitudinally extending sidebars interconnected by transversely extending crossbars at spaced points therealong, said crossbars being of a shape to fit within at least one of the portions of said H-shaped recess so as to interconnect two or more of said sliding contact means.
 20. A switch according to claim 19, wherein said housing structural elements are U-shaped having opposed side walls and a bottom wall interconnecting the same, a generally U-shaped cover adapted for engagement with the top portions of said side walls for closing said housing, and said cover having a leg portion adapted to engage said H-shaped recess on said top surface of said sliding contact means for engaging the same and sliding said sliding contact means into position in said housing.
 21. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, connecting means for connecting at least two of said sliding contact means in fixed relationship to each other so that movement of one sliding contact means will simultaneously effect the movement of said other sliding contact means connected thereto, a cover adapted to close the open-end of said U-shaped housing structural elements, said cover and said connecting means having complementary recesses and projections so that said connecting means can be positioned on said sliding contact means for interconnecting two or more sliding contact means without interference with said cover, said connecting means is adapted for connection to said sliding contact means at spaced apart distances equal to the distance between two adjacent pairs of fixed contacts such that upon positioning one of said interconnected sliding contact means adjacent one pair of said fixed contacts then the sliding contact means connected thereto by said connecting means will simultaneously also be in proper adjacent position with a pair of said fixed contacts.
 22. An electrical switch structure comprising: a housing including a plurality of U-shaped housing structural elements arranged in side-by-side relationship, said housing structural elements each having opposed side walls and a bottom wall, sliding contact means adjustably arranged within the housing structural elements for longitudinal movement therein, each housing structural element being provided with at least one pair of fixed contacts mounted therein, each sliding contact means being adjustable in a longitudinal direction to a position in any of the housing structural elements, each sliding contact means adapted to engage and electrically bridge only a single pair of fixed contacts at any one particular position, said housing includes end covers mounted at opposed ends of said housing, a mounting plate fixedly secured to each of said end covers with a portion projecting outwardly therefrom for engagement with a mounting surface for securing the switch thereto, said end covers including a tab projecting outwardly therefrom, said mounting plate having two recesses formed therein and adapted so that one recess will engage The tab in one position of said mounting plate with the other recess engaging the tab upon the reversal of the mounting plate 180*, said first recess being offset on said mounting plate from said second recess so that in a first position of said mounting plate said first recess will be engaged by said tab on said end cover with the bottom of said recess being flush with the bottom wall of said housing, and upon reversal of 180* of said mounting plate said second recess will be engaged by said tab at which time said mounting plate will project slightly outwardly beyond the bottom wall of said housing thereby effecting the spacing of said bottom wall from the mounting surface upon the mounting of said switch thereon. 